摘要
量子级联激光器的核心区由纳米级厚度的In_(x)Ga_(1-x)As/In_(y)Al_(1-y)As复杂啁啾超晶格结构组成,对薄膜厚度和材料组分具有极高的精确性要求。本论文定量分析了发射波长~4.6μm的四阱双声子结构量子级联激光器核心区材料组分及厚度对发射波长和增益性能的影响。模拟结果显示,当Ga通量偏差为±2%时,器件发射波长和性能几乎无变化;而In/Al通量仅偏移1%,波长偏移超过2%,品质因子衰减28 ps·A^(2)。此外,研究发现整体厚度减小5%时,核心区品质因子提升8%;势阱层厚度减小5%时,品质因子提升52%。有源区厚度增加10%时波长增加340 nm,品质因子下降33%;注入区厚度增加10%则导致核心区品质因子下降75%。注入势垒和出口势垒的调整会导致核心区品质因子恶化,且出口势垒厚度增加对品质因子的影响更为严重。根据模拟结果总结了发射波长的控制手段及提高核心区性能的方法,对激光器波长控制及理论性能提升具有重要的指导意义。
The core region of quantum cascade lasers consists of a complex chirped superlattice structure of InxGa_(1-x)As/In_(y)Al_(1-y)As with nanometer thickness,which requires a very high degree of accuracy in terms of layer thickness and material composition.In this study,a quantitative analysis is conducted on the influence of material composition and thickness in the core region of a four-quantum-well double-phonon structure quantum cascade laser emitting at~4.6μm on its emission wavelength and gain performance.The simulation results show that the emission wavelength and performance are almost unchanged when the Ga fluence shift is±2%.In contrast,the wavelength is shifted by more than 2%when the In/Al flux varies by more than 1%,with a maximum Figure of Merit(FOM)attenuation of 28 ps·A^(2).In addition,it shows that a 5%reduction in the overall thickness increases the FOM by 8%,and a 5%reduction in the thickness of the barrier layers increases the FOM by 52%.A 10%increase in the thickness of the active region results in an increase in wavelength of 340 nm and a decrease in FOM by 33%,while a 10%increase in the thickness of the injection region results in a 75%decrease in FOM.Adjustment of the injection and exit barriers degrades the quality factor of the active region,and increasing the thickness of the exit barrier has a powerful effect on FOM.According to the simulation results,the means of controlling the emission wavelength and improving the performance of the core region are summarized,providing significant guidance for wavelength control and theoretical performance improvement in quantum cascade lasers.
作者
杜舒豪
郑显通
冯玉林
柳渊
张东亮
刘铭
DU Shu-hao;ZHENG Xian-tong;FENG Yu-lin;LIU Yuan;ZHANG Dong-liang;LIU Ming(Laboratory of Optoelectronic Materials and Devices,Beijing Information Science and Technology University,Beijing 100192,China;11th Research Institute of CETC,Beijing 100015,China)
出处
《激光与红外》
北大核心
2025年第11期1680-1686,共7页
Laser & Infrared
基金
北京市教育委员会科技计划项目(No.KM202211232015)资助。
